Summary The STRIDE Trial is the largest pragmatic, cluster randomized, parallel group superiority trial with practices stratified by healthcare system and patients nested within practices. Fall injuries are a major public health problem. This randomized trial will determine the effectiveness of an evidence-based, multifactorial, patient- centered intervention to reduce the risk of serious fall injuries among non-institutionalized older persons. The original target sample size was 6,000 participants enrolled from 86 practices to provide 90% power to detect a 20% reduction in the rate of the primary outcome with intervention relative to control. Later, the duration of the trial was extended to a total of 40 months (20 months of recruitment and an additional 20 months of follow-up), which reduced the target sample size to 5,322 participants. Recruitment ended after 20 months on March 31, 2017, with a total of 5,451 participants enrolled. The intervention phase ended on November 30, 2018 and follow-up ended on March 31, 2019. The primary aim of this administrative supplemental application is to request funds to carry out trial close-out activities necessitated by the extension of the intervention and the follow-up period as a result of the two DSMB-approved modifications in the trial's design. First, in December 2017, the trial's DSMB and the NIA approved the extension of the duration of the study from 36 months (18 months of recruitment and a minimum 18 months of follow-up) to 40 months (20 months of recruitment and a minimum of 20 months of follow-up). Second, based on an analysis of the event rate of the primary outcome in a closed session, the trial's DSMB and the NIA staff directed the study team to Extend the study from a minimum of 20 and maximum of 40 months follow-up to a minimum of 24 and maximum of 44 months of follow-up. Because of the extension of the intervention duration and the follow-up period, the project's end date was extended to April 30, 2020. The close-out funds are necessary for completing the data cleaning, adjudication of the primary outcome, analyses of the primary and secondary outcomes as described in the peer-reviewed and funded grant application, preparation of the study reports and manuscripts, and orderly close-out of the trial. The supplement does not change the specific aims or scope of the parent grant application and is required for implementing the DSMB and NIA-approved extension of the intervention and follow-up period, and the trial's close-out activities. In august 2018, the NIA and PCORI approved the request for additional funds in the amount of $3,365,602. The first tranche of $2.065,602 has been released by NIA. This application requests the release of the remaining $1,300,00 of to support the study's close out activities associated with study's extension to April 30, 2020.